Synchrotron-based in situ X-ray absorption near-edge structures have revealed the unique lithium reaction pathway and storage mechanism, which is supported by density functional theory based calculations.Dendrobium hercoglossum Rchb. f. (D. hercoglossum), as one of the origins of medicinal Dendrobium, has been widely used as a health food and nutrient source promoting fluid production. Due to a lack of quality control, it is often counterfeited or mixed with other Dendrobium. In this study, a high-performance liquid chromatography characteristic chromatogram method is established for the quality evaluation of D. hercoglossum. Based on the high-performance liquid chromatography characteristic chromatogram, D. hercoglossum is divided into two classes, each with different flavone peaks. These flavone peaks were identified using high-performance liquid chromatography coupled with electrospray ionization multistage tandem mass spectrometry. Among them, the acylated (3-hydroxy-3-methylglutaryl, p-coumaroyl, feruloyl, or sinapoyl) flavones-C-glycosides are first found in D. hercoglossum in this study. In addition, one unique band was found in D. hercoglossum by thin-layer chromatography, which can be used to distinguish it from other Dendrobium species as a characteristic marker of this plant. Combining the high-performance liquid chromatography characteristic chromatogram and high-performance liquid chromatography coupled with electrospray ionization multistage tandem mass spectrometry, the unique band was identified as 4,5-dihydroxy-3,3'-dimethoxybibenzyl. These analysis methods can be applied for the quality control and identification of D. hercoglossum as well as providing reference for the identification of similar constituents in other Dendrobium species.Rational design of low-cost, highly efficient, and stable electrocatalysts for the hydrogen evolution reaction (HER) has attracted wide attention. Herein, 3D RuCu nanocrystals (NCs) are successfully synthesized by a facile wet chemistry method, in which amorphous RuCu nanosheets are directly grown on crystalline Cu nanotubes (NTs). Importantly, the obtained 3D RuCu NCs only need 18 and 73 mV to deliver the current density of 10 mA cm-2 for HER in alkaline and neutral media, respectively. https://www.selleckchem.com/products/fsen1.html Density functional theory calculations and experiments reveal that the Ru sites on the surface of amorphous nanosheets are the highly active centers for HER. Moreover, this catalyst can expose more surface area for water splitting compared to pure nanosheets because the unique 3D structure can effectively prevent the aggregation of nanosheets. Meanwhile, the interface between amorphous nanosheets and crystalline NTs is essential to boost the HER performance because the amorphous phase with many unsaturated bonds can facilitate adsorption of reactants and crystalline Cu with superior conductivity can promote the transfer of electrons. This work provides a facile method to prepare an original 3D Ru-based electrocatalyst with highly active HER performance in wide pH values.Drowning is a global public health challenge with a need to ensure equity to drowning prevention information and interventions. In Australia, people born overseas are identified as being at greater risk of drowning. This paper presents findings from a community-based qualitative evaluation of swimming and water safety (SWS) programs delivered to adults from migrant backgrounds in Sydney, Australia.
A qualitative study was conducted in November-December 2019 among 35 female participants of SWS programs targeted to adult migrants. While offered to all SWS program participants, no males took part in the study. Focus groups and interviews were recorded, transcribed and thematically analysed using a deductive approach. The domains of enquiry were guided by the health belief model and the theory of planned behaviour.
Study participants were ?25years, first generation and most had lived in Australia for ?10years. Most were nonswimmers and were fearful of water prior to the program. Key themes were direct SWS program outcomes, health and well-being; enablers and barriers to participation including motivation, a program coordinator, fear and settlement priorities.
Findings suggest that in order to increase SWS participation among migrant communities, the broader determinants of health need to be considered. Culturally appropriate strategies are required to enable both men and women equal opportunities to access SWS programs.
SWS programs provide multiple benefits for adult migrants; however, the impact on reducing inequities is limited, with broader multi-strategic health promotion approaches and policies required for inclusion and sustainability.
SWS programs provide multiple benefits for adult migrants; however, the impact on reducing inequities is limited, with broader multi-strategic health promotion approaches and policies required for inclusion and sustainability.The HPLC-DAD and GC/MS methods were successfully used for the identification and characterization of the impurities in an agrochemical insecticide, bifenthrin technical. Three impurities ranging from 0.175%-0.541% were detected by the HPLC-DAD method. The LC/MS technique with ESI or APCI source failed to detect the impurities detected by HPLC-DAD, due to lack of ionization in ESI or APCI. The three impurities were enriched by prep-HPLC, and then their structures were elucidated based on the GC/EIMS and CIMS data. The EI mass spectra of bifenthrin and its impurities displayed molecular ion and provided structure indicative fragment ions; the CIMS data further confirmed their molecular weight. The identity of the impurity 1 was further confirmed by the synthesis of the authentic sample followed by NMR and GC/MS data.A prolonged mismatch between the demand for respiratory muscle work and the capacity to meet that demand in chronic obstructive pulmonary disease (COPD) can result in symptoms of dyspnea and the development of muscle fatigue.
The purpose of this study was to compare two different respiratory muscle endurance assessment methods of sustainable inspiratory pressure (SIP) and incremental threshold loading (ITL) in COPD.
Thirty-four patients diagnosed with COPD were included in the study. Physical and demographic characteristics of the subjects were recorded. Pulmonary function testing (PFT), modified Medical Research Council (MMRC) dyspnea scale, COPD assessment test, inspiratory and expiratory muscle strength (MIP and MEP, respectively) measurement and six-minute walk test (6MWT) were used to assess subjects. Two different respiratory muscle endurance tests (SIP and ITL) were performed within 48 hours apart, and each test was repeated two times on the same day.
There was no correlation between the SIP and ITL tests (r = 0.